Classic Ratatouille

1 eggplant, sliced into 1/4-inch rounds

2 zucchini, sliced into 1/4-inch rounds

1 yellow onion, thinly sliced

4 garlic, minced

1 red bell pepper, diced

1 yellow bell pepper, diced

4 thyme, sprigs

15 g basil, roughly chopped

800 g crushed tomatoes, canned

30 ml tomato paste

60 ml olive oil, divided

10 ml kosher salt, divided

5 ml black pepper, freshly ground